Good morning all
Just a little input please
I bought a nice shiny chrome alternator from Jegs £200 +
It’s a one wire alternator and I think its getting too warm, cant even hold your hand on it.
Checking the charging, I have found out its constantly charging. So I disconnected the one wire from my voltage regulator only for to find out its still charging with only the large red charging wire connected
Any thoughts please ?
Last edited by TIB3300 on Sun Jul 02, 23 6:26 am, edited 1 time in total.
Are you sure it has not got a built in regulator, most of single wire alternators I have used have had built in regulator. That said, I’m no expert in electrics.
"I spent a lot of money on booze, birds and fast cars. The rest I just squandered."
I thought a 1 wire alternator has to by its nature have a regulator and sense circuit in it already
it has to decide on its own how much it sticks into its field/rotor to get an appropriate output
it only has 1 contact with the outside world and that is the voltage it see's at the output stud and the current that flows
inside there is something that can judge if it should be on or off based on rpm voltage and current flowing
i.e won't be on below 1500 or so, presume there is some halle effect setup in there that provides pulses of some such to allow counting i.e rpm
won't be on even if the voltage is a bit low but current flow is minimal
will be on if voltage seen is below say 12.5 volts or if current is high
will switch off when the voltage gets to say 14.3V
need a good earth at the mounting or what it thinks is 14.3v isn't 14.3v and it will carry on chargeing when it doesn't need to.
Dave
The Greater Knapweed near the Mugwort by the Buckthorn tree is dying
mopar_mark wrote: ↑Thu Jun 15, 23 12:04 am
Are you sure it has not got a built in regulator, most of single wire alternators I have used have had built in regulator. That said, I’m no expert in electrics.
It’s a one wire alternator set up, as indicated in the picture. I use a Hella voltage regulator again pictured all was good last year.
Since asking my question here I have taken all the internals from last year’s alternator and put them inside the nice shiny new chrome alternator.
Dave999 wrote: ↑Fri Jun 16, 23 3:33 pm
I thought a 1 wire alternator has to by its nature have a regulator and sense circuit in it already
it has to decide on its own how much it sticks into its field/rotor to get an appropriate output
it only has 1 contact with the outside world and that is the voltage it see's at the output stud and the current that flows
inside there is something that can judge if it should be on or off based on rpm voltage and current flowing
i.e won't be on below 1500 or so, presume there is some halle effect setup in there that provides pulses of some such to allow counting i.e rpm
won't be on even if the voltage is a bit low but current flow is minimal
will be on if voltage seen is below say 12.5 volts or if current is high
will switch off when the voltage gets to say 14.3V
need a good earth at the mounting or what it thinks is 14.3v isn't 14.3v and it will carry on chargeing when it doesn't need to.
Dave
Hello Dave
Sorry youve lost me here
Just to give more input on this. I now have a working alternator, BUT when I put a multimeter on it. I now have 15volts stored in the battery
Last edited by TIB3300 on Mon Jun 19, 23 9:49 am, edited 1 time in total.
OK so if you have 15 volts at the battery when alternator is full on
either
you have a poor earth for the regulator
you have a poor earth for the alternator
you have a poor earth for the unused field terminal
OR
the tollerances of alternator and regulator stack up in a really akward way which is over chargeing your battery and it will boil.
Or there is a fault with one or the other.
really needs to be less than about 14.6
battery will gas at 14.6 and 14.8 is too much
preume you have the output from the alternater connected to battery +
or have you done what chrylser did?
either way with running at say 1500 rpm
go looking for a poor earth connection volt meter set to DC volts or milivolts
start with regulator case to body and body to battery negative
other option is to bolt regulator mounting to the battery negative for a test and see where voltage at battery ends up at when you switch on fan and full beam.
if it centres around 14.5 it was an earthing problem with the regulator
Dave
The Greater Knapweed near the Mugwort by the Buckthorn tree is dying
Dave999 wrote: ↑Tue Jun 20, 23 9:38 am
if you are emasuring 15 volts at a standard car battery when its just sitting and the car is not running
id be suspicious about the meter....
what does it measure fot standard battery should be 1.5 volts for a simgle cell AA or similar
does it measuer 15 on any other car batteries?
if it doesn't boil over maybe you just have a wierd battery....
Dave
Morning Dave
I do like your input, did as you said and apparently my (multimeter) is rubbish. As it still reads 16v on my daily car.
The test was with the engine off.
It will however charge, ( unregulated going upto 17 volts when I rev the engine) if I put a positive wire direct to the alternator.
But as soon as I put the supply through the regulator nothing. I have also bought a new regulator to see it that was the problem, still not charging
but try a low wattage 12 volt bulb in the wire that comes from the supply to D+
it would normally be kinda blue and sit in your dash pod
it should go out when alternator switches on
the stud is field the middle one should be bolted down to body and the other one is D+
12 volts goes into D+ but some regulators like a bulb in that wire... regardless of if the regulator is remote or built into the back of a square back alternator with multiplug and loads of wires
The Greater Knapweed near the Mugwort by the Buckthorn tree is dying
